By Laura Pottorff, Colorado State University Cooperative Extension
agent, plant pathology and horticulture

Mistletoe suffers an identity crisis.

On the one hand it's a parasite that takes food from another plant,
such as ponderosa, lodgepole and limber pines. On the other, its inspires lots of
Christmas kisses, merriment and good times.

So, will the real mistletoe please stand!

Both mistletoes are real. Both plants grow on trees and rob them of
their food. Dwarf Mistletoe (Arceuthobium) grows in the Colorado foothills and mountains.
Leafy mistletoe grows in the American Southwest. Both can be very destructive to host
plants.

Dwarf mistletoe can cause branches to swell; it also can reduce the
amount of foliage (needles) that will grow on the tree and it promotes the formation of
witches brooms, a condition that occurs when side shoots begin to proliferate giving the
end of the branch a broom-like appearance.

Dwarf mistletoe takes some management, including the possible removal
of infected trees.

Then there's leafy mistletoe (Phoradedrum) which often grows on oak
trees in Arizona, New Mexico and Texas. It usually shows up around the holidays in small
cellophane packages with instructions to hang in a visible spot and let the action begin.

Where did the Christmas folklore surrounding mistletoe begin? The
pre-Christian Greeks knew about it and the Celts, early settlers in the British Isles,
dubbed it the "Celestial Tree," believing that it was rooted closer than all
other plants to the heavens. Druids, Celtic holy men, used mistletoe in rituals; hence the
plant took on importance before the beginning of the Christian era.

The mistletoe we use at Christmas also became linked to pagan
ceremonies involving the winter solstice. Once Christianity spread, mistletoe became
incorporated into Christmas celebrations. Thus began the linkage between mistletoe and
Christmas.

In addition to using mistletoe in holiday celebrations, ancient peoples
have used it as medicine; at one point mistletoe was even considered a preventive for
bubonic plague. Later it was associated with fertility. At present, however, its medicinal
value is questioned, although some research continues.

So, know your mistletoes. When you hike, ski or camp in the Rockies
next summer, look for a parasitic plant clinging to pine trees; likely it is dwarf
mistletoe. For now, however, hang that leafy mistletoe and stay ready: The magic of
Christmas may be about to begin!